1987 200hp Overheat Warning

[HornHarbor]

There is 5-6 week wait for engine repair so I'm trying to do what I can... Subject engine sounds overheat horn warning at start up but good water flow from tell tale and temp gauge stays low (does move up some). Local dealer mechanic said "pull thermostats and try it without them, probally only a stuck therm." Did that, didn't fix it... now will try to see if temp sensor is bad... Any suggestions/ideas...Thanks

 

[trumanlake]

Re: 1987 200hp Overheat Warning

What do you mean by "at start up"? Is it sounding as soon as you turn the key on? Have you checked the wire from the sender to the terminal block? Some times the isulation on the wire sort of cracks and can short on the block. You may try smacking the warning module(with a screw driver), see if that straightens it out, not that uncommon of a failure.

 

[kahuna]

Re: 1987 200hp Overheat Warning

Is it a continuous beep or short beeps?

 

[Thecol]

Re: 1987 200hp Overheat Warning

i have an 87 200 hp.i neverhd much luck with those warning horns.temp gauge'waterpressure gauge is all i rely on.possibly change t stats. or check water pump for wear.

 

[HornHarbor]

Re: 1987 200hp Overheat Warning

Thanks for the inputs... The horn sounds a loud continous beep NOT the oil injection beep. I know the sound of both... its the overheat BEEP! It sounds from the time the key is turned until the engine is shut off (I've heard it for 15 minutes straight ;-( ). I am going to try and test the sensor by the method in the repair manual. That failing I am just going to disconnect it and watch the temp gauge until I can get it looked at...now 5 weeks away ;-(.